1. Field of the Invention
This invention relates to electric trolling motors for boats, and more particularly, to a rotatably adjustable, "breakaway" bracket for trolling motors which includes a shaft bracket for carrying the shaft of the trolling motor; a bracket hinge which pivotally cooperates with the shaft bracket by friction engagement to facilitate downward rotation of the shaft and shaft bracket with respect to the bracket hinge when the shaft or submerged motor strikes an underwater obstacle, and a support bracket carried by the bracket hinge and mounted on the conventional trolling motor lift bracket attached to a boat. A primary feature of the trolling motor bracket is the "breakaway" function, which operates to prevent damage to the trolling motor shaft when the shaft or trolling motor strikes an underwater obstacle during normal operation. This breakaway feature is facilitated by a breakaway pin slot provided in the shaft bracket and at least one breakaway pin threaded in the bracket hinge in normal registration with the pin slot to permit application of a selected amount of pressure on the shaft bracket and control the pressure required to pivot the shaft bracket and shaft on the pivot pin. Another primary feature of the trolling motor bracket is the provision of rotation of the motor shaft with respect to the bow of the boat by means of the bracket hinge in order to compensate for substantially any type of trolling motor mount on the boat. Furthermore, the bracket can be mounted on substantially any conventional motor lift bracket. A specially designed insert can be used in cooperation with a preferred shaft bracket having a split housing in order to more positively engage, secure and adjust the trolling motor shaft in the shaft bracket, and to accommodate motor shafts of varying diameter.
2. Description of the Prior Art
Various types of brackets are known in the art for mounting motors to boats. Typical of these devices is the "Outboard Motor Bracket" disclosed in U.S. Pat. No. 2,264,364, to W. C. Conover. This bracket includes a vertically-oriented bracket member having a curved top portion attached to a motor and a clamp mechanism hinged to the bracket member for pivotally securing the motor to the transom of a boat. The motor can thus be pivotally raised from the water and locked into position, and allowed to pivot downwardly into the water, in functional position, as desired. Another motor bracket is disclosed in U.S. Pat. No. 4,094,482, to L. C. Weaver, and includes a mount having a base bracket for mounting the motor shaft of a trolling motor on a boat deck and swinging the shaft between a vertical operating position and a horizontal position over the deck. A clamping yoke for holding the motor shaft is swiveled on the bracket and a manually releasable latch which is pivoted on the bracket, selectively locks the clamping yoke in the respective operating and upward-pivoted positions when the yoke is swung to either position. A Trolling Motor Safety Mount for a trolling motor is included in U.S. Pat. No. 4,019,703 to Robert W. Meredith, which apparatus includes a clamp for attachment to the stern of a boat, a hollow mounting block pivotally mounted to the clamp, a detent device for maintaining the block in abutment with the clamp, and a latch for supporting the motor out of the water. The detent apparatus is designed to facilitate pivotal operation of the block with respect to the clamp upon striking of an underwater obstacle by the motor, in order to move the motor from engagement with the submerged obstacle.
One of the problems which is apparent regarding existing motor brackets, and trolling motor brackets for electric trolling motors in particular, is the lack of protection afforded the submerged motor unit and particularly, the motor shaft, from damage resulting in contact with underwater obstacles. These trolling motors are typically mounted on a folding bracket attached to the bow of a boat, and extend downwardly from the bow into the water. Accordingly, the pressure applied on the submerged motor and the extending shaft by a submerged stump, log or other obstacle as the boat is propelled by the trolling motor is a function of the speed and weight of the boat and occupants. Since many of the larger and heavier fishing boats are provided with powerful, 24-volt trolling motor systems for greater speed and effective operation of the boat in a wind, the momentum generated by the boat frequently causes the trolling motor shaft to bend when the motor or shaft strikes such an obstacle. Consequently, the shaft must either be straightened or replaced, at considerable expense. One effort to deal with this problem is featured in an electric trolling motor bracket developed by Motor-Guide Division of Arnold Industries, Inc., which includes curved and slotted guides supporting pins secured to the motor shaft support bracket and designed to facilitate a 30 degree pivot of the motor and shaft when an underwater obstacle is encountered.
Another problem frequently encountered in the use of conventional electric trolling motors is the mounting of the motor on the boat, which frequently requires that the top segment of the motor and shaft extend inside the hull area when the motor is in retracted configuration. This mounting arrangement requires interior space which could otherwise be used by the fisherman. Since conventional trolling motor mount brackets are rigid with respect to the retracting boat bracket, the boat bracket must be mounted in such a manner as to point the trolling motor generally forward of the bow, and depending upon the design of the boat, there is generally very little flexibility of choice in positioning the bracket on the bow of the boat.
Accordingly, it is an object of this invention to provide a universal trolling motor bracket which is capable of interfacing with substantially any conventional folding boat bracket, which trolling motor bracket is characterized by a "breakaway" function and a pivoting feature for protection of the trolling motor shaft and hinged adjustment of the trolling motor position with respect to the bow of the boat, respectively.
Another object of the invention is to provide a new and improved trolling motor bracket which incorporates a substantially unlimited "breakaway" function to protect the motor shaft from bending or breaking due to contact with underwater obstacles, which breakaway function is always essentially perpendicular to any such load applied to the submerged motor or shaft when the motor is propelling the boat forward.
Yet another object of this invention is to provide a new and improved trolling motor bracket which includes a shaft bracket having a split housing and, in a most preferred embodiment, a sleeve in the housing for adjustably gripping the motor shaft, and further including a rear slot means as one element of the "breakaway" function; a bracket hinge pivotally attached to the shaft bracket and having a pair of pins threadably attached thereto, the pins positioned for contact with the slot means in the shaft bracket and adjusting the friction-operated "breakaway" function of the shaft bracket; and a support bracket attached to the bracket hinge and to a conventional folding boat bracket mounted to the deck of a boat, the bracket hinge serving to permit rotational adjustment of the shaft bracket and the motor shaft with respect to the bow of the boat.